Pressure electric switch



Nov.1,1927. 1,641,949

J. F. wlNlLER PRESSURE ELECTRIC SWITCH Filed NOV. 16. 1921 Patented Nov. 1, 1927.

UNITED STATES reitera JOSEPH r. winirnnn, orrnrLnnnriiDn-rn, rnrtrisrrvanrn. j

i Application led November 16, 1921. `Serial No. 515,584.

One obj ect of my invention toprovide a pressure .controlled electric switch with novel-means whereby the movable contactof said switch shall bei-maintained in its closed position until it is automatically tripped by.

reason of fluid or gaseous pressurerising above` a predetermined point, and the in-y Vention further contemplates novel means whereby the resetting of said switch 1s preventeduntil the pressure of the fluid to be controlled hashfallen to a second predetermined point below that at which tripping of I saidswitch was caused. i 1 I i Another object of my invention 1s to provide novel means for controlling theauto shown in Fig. 1. Y

In the above .drawings,1 represents a suitable ldust-prooi 4containing casing, within which` is mounted a 'Bourdon tube ,connected `through a pipe3 tothe iiuidioontaining system whose oper-ation" is j ,toA be j controlled. The closed 4end of the tube 2is provided with a head 4 ypivoted byja pin 5 to one end of a lever 6;:Projecting from this lever adjacent its pivot 5 is a downwardly extending arm 7 having connected to it :one end of a spring 8, whose `opposite endlisfixed tor a post 9 projecting from the back of the cas ing 1. Operative `.on theopposite side of said lever from the arm 7 is an adjustable fulcrumscrew 10 for setting the device as hereafter described. The free end of the a lever arm 6 extends between the branches of a fork 11 projecting from a trigger lever 12 fulcrumed on a pin 13 fixed to the back of the casing and having a downwardly projecting arm 14 and a hooked head 15; the 5 arrangement being such that the movement of the lever 6 tends to operate thetrigger lever 12 on its pivotpin 13.

Rotatably mounted on this pin is a disc 16 having a radially formed slot 17 and provided withV a projecting pin 18 positioned to cooperate with the arm 14 of the lever 12 Fi g.2 is a side elevationof the apparatus under centain conditions.V Thisdisc 16 at all timestends to rotate in a counter clockdle v13 under theacti-on 'of a spring '19 connected'to its pin k18 and hooked to the trigger lever 12.

Slidably mounted in the casing structure 1 is a manually operativegsetting plunger 2O in the form of apush rodl normally maintained in an elevated position by a spring "21 operative between its head 20a and a guide bearing 22 carried by Vthe casing. The lowerend of this plunger rod carries a U- shaped yoke23 between whose armslis jour nalleda roller ,23a capable of `engaging with 2O in its depressed positionV against the action of its spring 21. Said roller is also capable of entering theslot 17 of therdisc 16 when this latter is in a predetermined position.

j Carried by the plunger rod 20 is the movable contact 24of an' electric switch which inthe present instance is of the multiple vcontact type,v having va pairof lower fixed contacts2525and`a pair of upperiixed contacts 264426. When said plunger 20 has been so.far'depressedthat its roller is `en- .g-'aged by the hook. or trigger 15,- the movable contact 24 engages the lower contacts 25425,

the spring21 actstovelevate the.` plunger rod toits upper position in. which the movable contact 24 'engages the upper fixed contacts KUnder,.conditions of usefas longaszthe pressure inthe Bourdon tuberemains belowV 'ag predetermined amount, it is possible to depress theplunger rod 20V so as to causeits 'roller .238*` to engage and be held down by ;theftrigger so .thattheswitch contacts -turns the lever12 on its pin 13 and disengages thehook 15 from the roller carried bythe plunger rod 20,1thereby permitting the plunger rod to rise,`disengaging the contact 24 from the switch contacts2525 and Acausing.saidcontact to connect the contacts At `the same time this turning of the `lever 12 and the resulting upward movement of the roller out of the slot 17 leaves .wise direction on its supporting pin or spinthe trigger lever 15 tol hold the plunger rod Y butwhen said trigger disengages said roller,

the disc 16 free to be turned in a counteri l clockwise direction on itsl spindle 13 under the action oi the spring 19, thus causing the' pin 18 to follow the lever 12 until it engages the arm 1e thereof. The slot -17 is now out oi the line of movement'of the roller, so that even though the plunger rod 20 be moved wiserdirection, whereupon its arm 14: engages the'pin 18 and restores the disc 16 to such` a position that'the roller on the plunger rod may again be moved into the slot 17. Under these conditionsg-when said plunger rod is depressed, the roller acts on the head of the trigger 15, displacing this and moving lunder it into its engaging position shown in the drawings,'thus holding the plunger 2O down and retaining the switch contact 24 in engagement with thel lower xed contacts 25-25. 1

I claim:` 1. The combination with an electric switch 'of a push rodv carrying the movable contactoi said switch' and having a projecting part; a trigger' leverinovable in response to .engaged by Vthe trigger lever. "2: The combination with an electric switch of push rod carrying the movable Contact Huid pressurevariations inA a system to be .controlledy and positioned to engage the projection to normally hold the Vpush rod with thel switch closed ;1 with a rotary member yautomatically'movable into positionto prevent resetting'of the push rod and; closure of 'the switch after said Arod has been of'saidswitch and having aprojecting part;

trigger lever Vmovable in response to-luid pressure variations in a system to be controlled v and nositioned tofenffade the ro- Y b D jection to normally hold-the push rod with the switch Aclosed/ya rotary member automatically movable into position toV prevent the switch after ysaidrod has been disengaged by the trigger lever with means for rotating said member into position to permit resetting of the push rod when the pressure has fallen to a predetermined point.

3. The combination with an electric switch Aoit a pushrod carrying the movable Contact .predetermined point; a. rotary member having a slot positioned to receive the project- -ing part ot the push rod when it is engaged by the trigger lever; and means for causing 1 rotation of said member when saidvprojecting part moves out of its slot to` prevent resetting ot' the push rod and closure of the vswitchJ 4.y The combination with an electric switch of a push rod carrying theniovable contact of said switch and having a projecting part; y j a pressure responsive element; a trigger lever-actuated by said element and positioned to engage the projection to hold the push rodwith the switch closed asflong as the pressure acting on said element is below a predetermined point; a rotary member hav! ing a slot positioned to receive the projecting part of thepush rod when it is engaged by thetrigger lever; ,and means forcausing rotation of said member when said projeot- ,v i

ing part-moves out ofl its slot, said trigger lever including apart 'for restoring the ro- Vtary'member to fa position Vto receive said r`projecting parte when the pressureffalls to di'sa predetermined point.

' 5. vThecombination with an electric switch i of a pressure actuated member; means" controlled vby.' said member for holding the vswitch-closed until the pressure-rises above a predetermined point; with means for pre-V t ventingclosure of the switch until the pressure.- falls f below another predetermined point, said last mentioned means being actuated in onedirectionby said first menn l j Vtionedmeans.'v Y f resetting Vof the pushjrod and closure of 

